Stretching tool



March 1952 s. R. DUMMER 2,588,501

STRETCHING TOOL Filed Aug. 15, 1946 IN VEN TOR.

5A MUEL R. HUMMER 67 5 A TTORNEY I Patented Mar. 11, 1952 UNITED STATES1 Claim. 1

This invention relates to new and useful improvements in stretchingtools and has particular relation to a tool for stretching screen wirenetting over framed openings.

An object of the invention is to provide a tool adapted to convenientlyand quickly stretch and hold over'a framed opening, without distortionand at the desired tension, screen wire netting which has previouslybeen cut to a required size.

Another object is to provide a tool of the character outlined and which,when applied, will hold the overlying edge portion of the screen nettingclosely adjacent to the frame leaving the operator free to employ bothhands in tacking or otherwise securing the screen netting. in place.

A further object is to provide a tool having the advantages aboveoutlined and which is easily adjusted and which when supplying tensionto the screen netting to be fastened to a frame will not be loosened orfreed from its adjusted position by a shock or jar or the like and whichwill retain itself in the position desired.

An additional object is to provide a stretching tool having theadvantages indicated and which may be inexpensively manufactured as bydiecasting or the like, whereby assembly is permitted without thenecessity for expensive machining operations.

Other objects and advantages of the invention will become apparent froma consideration of the. following detailed description taken inconnection with the accompanying drawing wherein a satisfactoryembodiment of the invention is shown; However, it is to be understoodthat the invention is not limited to the details disclosed but includesall such variations and modifications as fall within the spirit of theinvention and the scope of the appended claim.

In the drawing:

Fig. 1 is a view showing the tool of the invention is substantially fullsize, and as employed in holding a screen netting in place over a framedopening;

Fig. 2 is a top or plan view of the tool alone;

- Fig. 3 is a front elevational view of the tool;

Fig. 4 is a vertical central sectional view through the jaw forming apart of the tool;

Fig. 5 is a front elevational view of the pressure plate employed: and

Fig. 6 is an isometric View, looking from the rear of the pressure plateof Fig. 5.

Referring in detail to the drawing, the tool of the invention comprisesa body generally designated I and including an elon ated platelike body.I I, laterally enlarged at its forward end and carrying a pair ofoutwardly directed parallel side portions or ears I2 and I3. Theseportions or ears I2 and I3 are spaced from the bodv I I toward theextreme forward end of the latter whereby openings or notches H! areprovided for the'entrance of wire screen or wire netting I over theupper forward portion of the plate-like body II.

The ears I2 and I3 provide for the pivotal mounting of a clamping jaw I6shown as formed 'of a single piece of metal and including parallel sidewalls I1 and I3, a handle or finger portion I9, and a, rounded cam-likegripping'portion 20. This jaw I6 is located between the ears I2 and I3and has its side walls I1 and H3 in parallel relation with said ears.Rivets or equivalent means 2! pass through the ears I2 and I3 and thewalls I! and i8 and pivotally mount the jaw It on the body ID.

with the described construction it will be understood that when the jawI6 is rocked from the position of Fig. 1, by lifting up on the handle orfinger portion IS, the gripping portion 20 will move rearwardly andupwardly away from the forward or jaw portion 22 of the body I I.Therefore, when a screen, or a portion of a screen, is located over saidjaw portion 22 and the jaw I6 rocked in the opposite direction bypressing downwardly on the handle or finger portion I9 a portion of thescreen will be clamped against the jaw 22 by the clamping portion 20 ofthe jaw I6. This clamping portion 20 is on a radius the center of whichis rearwardly of the pivots 2| when screen is clamped and when the clampis released. Thus, the clamp does not move through a dead center and iseasily flipped up to released position and is easily moved down toclamping" position.

Slidable longitudinally on the body II is a pressure plate generallydesignated 23. Such pressure plate comprises a forward plate-likeportion 24 having a pair of short prongs or projections 25 on itsforward face and also in its forward face is a V-shaped notch or groove26. Toward its upper end plate 24 is provided with a T-shaped recessZ'I,the horizontal portion of which is of the width of the body II and thevertical portion of which is of a width equal to that portion of thebody II located between the pair of notches 28'. g

7 On the rear side of the plate 24 is a housing or extension 29 having asocket 30 opening through its upper and lower or bottom side and havinga slot 3| in its rear wall and communicating with the said socketthrough the upper edge of said wall. The pressure plate 23 is as embledto the body I I by first inserting the shank 33 of the adjusting screw34 into the tapped hole in the thickened portion or boss 32 until thereduced diameter 35 projects far enough through to be slipped into theslot 3| of the pressure plate 23. then the pressure plate is pushed upthrough the notches 28 in body II and a few turns of the adjusting screw34 will push the pressure plate forward alon the bodv II. When this hasbeen accomplished, the lateral edges of the body II are located in theextremes-of the cross portion of 3 the inverted T-shaped slot 21 so thatthe pressure plate 23 is adjustable along or longitudinally of the bodyI I but will not rock relative thereto.

On its other or rear end, the body II is provided with a thickenedportion or boss 32 having a tapped hole therethrough and through whichis threaded the shank 33 of the adjusting screw, generally designated34, having a head in the form of a wing nut, as shown at 35. Towards itsinner end the shank 33 is provided with a reduced diameter portion 36located in the slot 3| in the rear wall of the housing-like portion 29of the pressure plate and beyond said reduced diameter portion saidscrew shank includes a head 31 the same diameter as the shank 33.

Clearly, as the adjusting screw 34 is rotated it will be fed through thetapped hole in the thick ened portion or boss 32. With thisconstruction, it will be apparent that when the pressure plate 23 isattached to the adjusting screw 34 and that by rotating such screw inone direction the pressure plate wil lbe moved forward along the body IIand that by rotation of said screw in the opposite direction thepressure plate will be moved rearwardly along said body I I.

When using the tool of the invention, as for example, to adjust the toolto stretch the Wire screen or netting I over the bar 38 of the frame(shown in section), the adjusting screw 34 is rotated to draw thepressure plate 23 rearwardly on the body II to the required distance.Then the tool is disposed on the frame with the pressure plate againstthe outer edge of the frame 38 and with the forward portion of the bodyI I projecting over said frame member so as to receive an edge portionof the screen I5 over the jaw portion 22.

Then the clamping jaw I6 is rocked downwardly on the pivots H as to theposition of Fig. 1, clamping a portion of the screen against the jaw 22.Now the operator rotates the adjusting screw 34 in a direction toadvance the pressure plate along the body I I. As the plate contacts theframe the prongs 25 will first enter the frame member. Then as turningof the screw continues, the pressure plate being unable to advance, thebody II and parts thereon is drawn outwardly or rearwardly over theframe piece 38 drawing the clamped edge of the screen over such framepiece. When the screen is adjusted to the desired tension, turning ofthe adjusting screw 34 is discontinued.

and the operator has both hands free to tack or otherwise fasten theedge of the screen netting to the frame member 38. A shock or jolt willnot cause the tool to jump up or come loose from its position as thespikes or prongs 25 are embedded in the frame member and in addition,the face of the pressure plate 24 is flat against the frame member andthe pressure is considerably below the upper surface of the latter alongwhich the pull, occasioned by the tension of the screen netting, isexerted. When the screen netting has been tacked in place, clamp I6 isreleased and the entire tool moved to a new position.

The V-shaped notch or groove 26 in the face of the pressure plate 24provides for the mounting of the tool on an external corner of a framewhich is being screened to square up the screen mesh or remove wrinkles.In such instance, the external corner of the frame is received in thenotch or groove 23 to prevent side-slipping of the tool and the tool isoperated by rotating the screw 34 as previously described. When the toolis used on the side of the frame, the operator forces the prongs 25 intothe frame as he turns the screw and after that is done the operation ofthe tool is concerned solely with the drawing rearwardly of the body IIand the clamp carried thereby. When the device is applied to theexternal corner of the frame, the sole operation is the rearward oroutward movement of the body I I and the clamp carried thereby.

While the invention has been described with particular reference to thestretching in place of wire screen or screen netting, both old and new,and particularly when that material has been cut to required size, itwill be understood that the tool may be used for stretching canvas,heavy fabrics, green animal skins, etc. As the tool provides means forstretching pre-cut wire screening over a frame, it will be understoodthat the trimming of excess screening from the frame is avoided. Thepresent tool consists of four parts, all of which are of ruggedconstruction and which lend themselves to manufacturing by die-castingmethods.

Having thus set forth the nature of my invention, what I claim is:

In a hand tool for stretching wire screening and the like over a frameopening and holding the screening in place and in stretched conditionwhile it is being tacked to the frame, a pressure plate having avertical frame-engaging face and a horizontal way therethroughdownwardly of its upper edge, an elongated body extending through andslidably guided in said way against all but longitudinal movementsrelative to said plate having a horizontal frame-engaging lower surfaceat right angles to said face of said plate, the upper surface of theinner end portion of said body plane and flat and comprising a jaw, asecond jaw, means pivoting said second jaw on the forward portion ofsaid body for swinging movement to and from clamping relation with thefirst mentioned jaw, said second jaw having a smooth rounded bottomclamping portion eccentric to its pivot, the outer end portion of saidbody extending downwardly in substantially parallel relation with saidvertical frame-engaging face of said pressure plate, a horizontal screwthreaded through said body portion and connected with said pressureplate for turning movement relative thereto whereby turning of saidscrew causes relative movement of said pressure plate and said body inthe direction of the length of the latter, and prong means on saidvertical frame-engaging face of said pressure plate below said way fordigging into the edge of a frame member to anchor the clamp thereto.

SAMUEL R. DUMMER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 324,673 Ehrenfeld Aug. 18, 1885348,833 Eckerson Sept. 7, 1886 598,413 Evans Feb. 1, 1898 827,257Murrell July 31, 1906 1,053,978 Ellsworth Feb. 25, 1913 1,239,479 HansonSept. 11, 1915 1,466,523 Donoho Aug. 28, 1923 1,514,149 Frizzell Nov. 4,1924 2,108,638 Benedict Feb. 15. 1938

